Smart nanoporous metal–organic frameworks by embedding photochromic molecules – state of the art and future perspectives

The zeolitic imidazolate frameworks ZIF-8 and ZIF-67 harbour a series of fascinating stimuli responsive properties. Looking at their responsitivity to hydrostatic pressure as stimulus, open questions exist regarding the isotropic compression with non-penetrating pressure transmitting media. By applying a state-of-the-art high-pressure powder X-ray diffraction setup, we revisit the high-pressure behaviour of ZIF-8 and ZIF-67 up to p = 0.4 GPa in small pressure increments. We observe a drastic, reversible change of high-pressure powder X-ray diffraction data at p = 0.3 GPa, discovering large volume structural flexibility in ZIF-8 and ZIF-67. Our results imply a shallow underlying energy landscape in ZIF-8 and ZIF-67, an observation that might point at rich polymorphism of ZIF-8 and ZIF-67, similar to ZIF-4(Zn).

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Revisiting the High-Pressure Properties of the Metal-Organic Frameworks ZIF-8 and ZIF-67

10.26434/chemrxiv.13146278 ◽

2020 ◽

Author(s):

Pia Vervoorts ◽

Stefan Burger ◽

Karina Hemmer ◽

Gregor Kieslich

Keyword(s):

High Pressure ◽

State Of The Art ◽

Energy Landscape ◽

Structural Flexibility ◽

Zeolitic Imidazolate Frameworks ◽

Stimuli Responsive ◽

X Ray Diffraction ◽

X Ray ◽

Open Questions ◽

Metal Organic

The zeolitic imidazolate frameworks ZIF-8 and ZIF-67 harbour a series of fascinating stimuli responsive properties. Looking at their responsitivity to hydrostatic pressure as stimulus, open questions exist regarding the isotropic compression with non-penetrating pressure transmitting media. By applying a state-of-the-art high-pressure powder X-ray diffraction setup, we revisit the high-pressure behaviour of ZIF-8 and ZIF-67 up to p = 0.4 GPa in small pressure increments. We observe a drastic, reversible change of high-pressure powder X-ray diffraction data at p = 0.3 GPa, discovering large volume structural flexibility in ZIF-8 and ZIF-67. Our results imply a shallow underlying energy landscape in ZIF-8 and ZIF-67, an observation that might point at rich polymorphism of ZIF-8 and ZIF-67, similar to ZIF-4(Zn).

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On the Use of MOFs and ALD Layers as Nanomembranes for the Enhancement of Gas Sensors Selectivity

Nanomaterials ◽

10.3390/nano9111552 ◽

2019 ◽

Vol 9 (11) ◽

pp. 1552 ◽

Cited By ~ 3

Author(s):

Weber ◽

Graniel ◽

Balme ◽

Miele ◽

Bechelany

Keyword(s):

Thin Films ◽

Gas Sensors ◽

Gas Sensing ◽

Metal Organic Frameworks ◽

Atomic Layer ◽

Operational Performance ◽

Layer Deposition ◽

Metal Organic ◽

Further Development ◽

Different Gases

Improving the selectivity of gas sensors is crucial for their further development. One effective route to enhance this key property of sensors is the use of selective nanomembrane materials. This work aims to present how metal-organic frameworks (MOFs) and thin films prepared by atomic layer deposition (ALD) can be applied as nanomembranes to separate different gases, and hence improve the selectivity of gas sensing devices. First, the fundamentals of the mechanisms and configuration of gas sensors will be given. A selected list of studies will then be presented to illustrate how MOFs and ALD materials can be implemented as nanomembranes and how they can be implemented to improve the operational performance of gas sensing devices. This review comprehensively shows the benefits of these novel selective nanomaterials and opens prospects for the sensing community.

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Negative linear compressibility in nanoporous metal-organic frameworks rationalized by the empty channel structural mechanism

Physical Chemistry Chemical Physics ◽

10.1039/d1cp00214g ◽

2021 ◽

Author(s):

Francisco Colmenero

Keyword(s):

Crystal Structures ◽

Metal Organic Frameworks ◽

Structural Mechanism ◽

Nanoporous Metal ◽

Metal Organic ◽

Linear Compressibility

Cobalt squarate hydroxide (Co3(C4O4)2(OH)2), zinc squarate tetrahydrate (ZnC4O4·4 H2O) and titanium oxalate trioxide dihydrate (Ti2(C2O4)O3·2 H2O) are nanoporous metal-organic frameworks possessing empty channels in their crystal structures. The crystal structures...

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Porosimetry for Thin Films of Metal–Organic Frameworks: A Comparison of Positron Annihilation Lifetime Spectroscopy and Adsorption‐Based Methods

Advanced Materials ◽

10.1002/adma.202006993 ◽

2021 ◽

pp. 2006993

Author(s):

Timothée Stassin ◽

Rhea Verbeke ◽

Alexander John Cruz ◽

Sabina Rodríguez‐Hermida ◽

Ivo Stassen ◽

...

Keyword(s):

Thin Films ◽

Positron Annihilation ◽

Metal Organic Frameworks ◽

Positron Annihilation Lifetime Spectroscopy ◽

Positron Annihilation Lifetime ◽

Metal Organic

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Nanomedicine-Based Strategies Assisting Photodynamic Therapy for Hypoxic Tumors: State-of-the-Art Approaches and Emerging Trends

Biomedicines ◽

10.3390/biomedicines9020137 ◽

2021 ◽

Vol 9 (2) ◽

pp. 137

Author(s):

Chun-Yan Shih ◽

Pei-Ting Wang ◽

Wu-Chou Su ◽

Hsisheng Teng ◽

Wei-Lun Huang

Keyword(s):

Photodynamic Therapy ◽

State Of The Art ◽

Metal Organic Framework ◽

Basic Knowledge ◽

Future Perspectives ◽

Effective Strategies ◽

Emerging Trends ◽

Tumor Tissues ◽

Metal Organic ◽

Manipulating Hypoxia

Since the first clinical cancer treatment in 1978, photodynamic therapy (PDT) technologies have been largely improved and approved for clinical usage in various cancers. Due to the oxygen-dependent nature, the application of PDT is still limited by hypoxia in tumor tissues. Thus, the development of effective strategies for manipulating hypoxia and improving the effectiveness of PDT is one of the most important area in PDT field. Recently, emerging nanotechnology has benefitted progress in many areas, including PDT. In this review, after briefly introducing the mechanisms of PDT and hypoxia, as well as basic knowledge about nanomedicines, we will discuss the state of the art of nanomedicine-based approaches for assisting PDT for treating hypoxic tumors, mainly based on oxygen replenishing strategies and the oxygen dependency diminishing strategies. Among these strategies, we will emphasize emerging trends about the use of nanoscale metal–organic framework (nMOF) materials and the combination of PDT with immunotherapy. We further discuss future perspectives and challenges associated with these trends in both the aspects of mechanism and clinical translation.

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